PCB a Week 17: USB Spypow

Mats continues his challenge of designing one PCB every week. In week 17 he came up with USB Spypow, it displays the actual charge rates of a USB device:

Yesterday I saw the “The Practical Meter” on Kickstarter – a small unit that is placed inline with the USB when charging your phone and shows the actual charging power (in watts) on a row of LEDs.
I wanted to have a go at it as well so I did the following last evening.